Verse 8 may be viewed as concluding the story of the birth of Isaac and also as a transition to the sending away of Hagar and her son. Verse 9 carries the transition another step forward. Translations differ in the way they relate verse 8 to its context. Good News Translation places it in a separate paragraph and has a heading before Gen 21.9. Revised Standard Version begins a new paragraph with verse 8 and continues that paragraph to verse 15. Some translations like New English Bible make no paragraph break at verse 8 or 9. (Note, however, that Revised English Bible opens verse 9 with a new paragraph.)
We may consider verse 8 as closing the story of Isaac’s birth (verses 1-7). In this case Good News Translation may be followed. It is also possible to take verse 8 as opening the episode of Hagar and Ishmael (verses 9-21). In this case it will be best to place the heading before Gen 21.8. This is done in Bible en français courant, Biblia Dios Habla Hoy, and Die Bibel im heutigen Deutsch. The Handbook follows the model of Good News Translation.
And the child grew, and was weaned: child translates a Hebrew noun that generally refers to a small child or infant. The same term will be used in reference to Ishmael in verses 14-16. Weaned refers to the process of accustoming a child to eat and drink without sucking from the mother’s breast. According to the story in 2 Maccabees 7.27, this was at the age of three. Most languages have terms meaning to wean, but if a descriptive phrase is necessary, it may be possible to say, for example, “and ceased drinking his mother’s milk,” “was taken off the mother’s breast,” “stopped sucking the breast.”
Abraham made a great feast: feast translates a term related to the word meaning “to drink,” reflecting the fact that feasts were occasions for drinking wine. However, in many cultures the essence of feasting is that a quantity and range of food is available, far beyond what is normally eaten. In such cases great feast may be expressed as “a big party for many people with all kinds of food.” The significance of the feast in this story is as a celebration of Isaac reaching his first stage in becoming a young man. Translators should make it possible for their readers to recognize this, whether or not the time of weaning is an occasion that is celebrated in their own culture; for example, “On the day when Isaac left the breast, Abraham made a big feast to mark [celebrate] the occasion.”
On the day that Isaac was weaned may sometimes be rendered “When Isaac was old enough to get along without his mother’s breast,” “When Isaac no longer drank from his mother’s breast,” or “When they cut him off from his mother’s milk.” In many languages there is a regular expression for the time of weaning, such as “let go the breast” or “leave the breast.”
Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .